1. Field of the Invention
The present invention relates to a method of manufacturing a nitride semiconductor light emitting device and a nitride semiconductor light emitting device manufactured using the method, and more particularly, to a method of manufacturing a nitride semiconductor light emitting device using a mask layer for growth on the basis of light emitting device chips and a nitride semiconductor light emitting device manufactured using the same.
2. Description of the Related Art
A light emitting diode (LED) is a semiconductor light emitting device that emits light of various colors by recombination of electrons and holes in a p-n junction between p-type and n-type semiconductors when a current is applied to the LED. When compared with a filament-based light emitting device, the LED has longer lifetime, low power consumption, excellent initial driving characteristics, high vibration resistance, and high tolerance for repetitive power switching. Thus, there has been an increasing demand for the LEDs. These days, group III nitride semiconductors that can emit light in short-wavelength region, such as a series of blue, have attracted attention.
In general, indium gallium nitride (In1-xGaxN, 0<x<1) among group III-V nitride semiconductors can generate light in the visible ray region to the UV region according to the indium (In) content. Further, the indium gallium nitride is widely used as a quantum well of an LED or a laser diode (LD).
FIG. 1 is a cross-sectional view illustrating a general nitride semiconductor light emitting device.
Referring to FIG. 1, a nitride semiconductor light emitting device 10 includes an n-type nitride semiconductor layer 12, an active layer 13, and a p-type nitride semiconductor layer 14, which are sequentially formed on a sapphire substrate 11. Further, n-type and p-type electrodes 15a and 15b are formed on a region formed by mesa-etching the n-type nitride semiconductor layer 12 and the p-type nitride semiconductor layer 14, respectively.
As such, in the nitride semiconductor light emitting device 10, a hetero substrate such as a sapphire substrate is generally used as a nitride semiconductor single crystal growth substrate.
Here, the nitride semiconductor single crystal has high defect density due to stress caused by lattice mismatching with the hetero substrate, which leads to a reduction in electrical and optical characteristics.
Recently, there has been a need for the use of nitride semiconductor light emitting devices in high-power apparatuses such as lighting apparatuses. Therefore, there has been a need for a method of improving an epitaxial layer forming a light emitting structure in quality and increasing luminous efficiency.